Micro-algae has been used for some time as colorants in the cosmetics industry and as food supplements. Recently scientists have been looking at the potential for refining micro-algae and they are emerging as a viable alternative to petroleum-based products. The development of efficient and scalable refining processes will make algae an increasingly attractive alternative.

The Algoroute project used bi-products from algae used in the cosmetics industry to create the bio-asphalt. Using hydrothermal liquefaction (pressurized water) the researchers turned the waste algae into a black, viscous, hydrophobic water repellant material. Although its chemical composition is very different from petroleum based asphalt, it exhibits similar performance properties.

The researchers are currently investigating the product’s performance over time and its potential for large scale production. The researchers believe that the use of algae not only negates the need for petroleum based products but also other oils derived from agricultural processes, which utilize land that would otherwise be used for food production.

The findings are published in the April issue of the ACS Journal for Sustainable Chemistry and Engineering.